1. Field of the Invention
The present invention relates to a display device employing an organic EL (electroluminescence) element.
2. Description of the Related Art
In recent years, research and development into making widespread use of display devices equipped with a light-emitting element type display panel where self-light-emitting elements such as organic electroluminescent elements (hereinafter abbreviated to “organic EL elements”) are arrayed two-dimensionally a reality as the next generation of display devices superseding liquid crystal display devices (LCDS) has been making considerable progress.
The organic EL elements include an anode electrode, a cathode electrode, and an electron injection layer, a light-emitting layer, and a positive hole injection layer etc. formed between these electrodes. Light is generated at organic EL elements as a result of energy generated by the recombination of positive holes supplied by the positive hole injection layer and electrons supplied by the electron injection layer at the light-emitting layer. Such organic EL elements are used as display devices as disclosed in Unexamined Japanese Patent Application KOKAI Publication No. 2001-195012 and the driven by, for example, TFTs (Thin-Film Transistors), etc.